Hello all, I am posting once again because I have run into a problem with my 83 trans am 305 where my gauge on my dash is reading a constant 18 volts when I start the car, my intuition points to a voltage regulator which is on the inside of the alternator, but I have replaced the alternator under warranty and the problem persists, the two prong connector on the alternator seems new so im also wondering if those wires being installed wrong would cause the internal regulator to go haywire. At this time the alternator is working, I am unsure what other things could cause this problem and any advice would help greatly.

 

The gauge could be way off. You'll need to test the alt with a volt meter and see what it's putting out at the connectors on the alt.